It is a beautiful, serene scene. The early morning(?) mist helps that feeling and conceals details, which makes the viewer look longer to try to discover or imagine them. The blue, grey, green palette is also quiet and introverted. The lake is like a mirror, with hardly a ripple.
Then there is the boy. He too is quiet and concentrating on his fishing and with one trouser leg pushed up, hints at a quiet, care-free attitude. He is also simply adding to the scene, and even though he contributes greatly, he is not the main subject. I have added a cropped version, which is also a nice quiet photo and may have been a tempting alternative, but it is about the boy and does not have the tranquility of your original, and comparing the two proves what a good choice you made in your framing.
